W83627DHG-PT Nuvoton Technology Corporation of America, W83627DHG-PT Datasheet - Page 74

• Manufacturer Part Number: W83627DHG-PT
• Manufacturer: Nuvoton Technology Corporation of America

Specifications of W83627DHG-PT

• Pin Count: 128
• Lead Free Status / RoHS Status: Compliant

8.7.3
The purpose of Caseopen function is used to detect whether the computer case is opened. This
feature must be able to function even when there is no 3VSB power. Consequently, the power source
for the circuit is from either Pin 74 (VBAT) or Pin 61 (3VSB). 3VSB is the default power source. If there
is no 3VSB power, the power source is VBAT. This is designed to save power consumption of the
battery.
When the case is closed, the signal of Pin 76 must be pulled high by an externally pulled-up 2MΩ
resistor that is connected to Pin 74. Once the case is opened, the signal will be changed from high to
low. Meanwhile, the detection circuit inside the IC latches the signal. As a result, the interrupt status
and the real-time status can be read at the registers next time when the computer is booted. The
status will not be cleared unless Bank 0, Index 46h, bit 7, or CR [E6h] bit 5 at Logical Device A is set
to “1” first and then to “0”.
8.7.4
The W83627DHG-P provides an alarm output function at the BEEP/SO pin. The BEEP/SO pin is a
multi-function pin and can be configured as BEEP output, if Configuration Register CR [24h], bit 1 is
set to zero.
The BEEP outputs a warning tone when one of the monitored parameters in the following events is out
of the preset range.
CASEOPEN#
CASEOPEN#
CASEOPEN
CASEOPEN
CASEOPEN
CASEOPEN
Any voltage input of the nine pins (CPUVCORE, VIN[0..3], 3VCC, AVCC , 3VSB and VBAT) is
out of the allowed range;
Any temperature input of the three pins (SYSTIN, CPUTIN and AUXTIN) exceeds the limit;
Any fan input of the five pins (SYSFANIN, CPUFANIN0, AUXFANIN0, CPUFANIN1 and
AUXFANIN1) exceeds the limit;
CASEOPEN# input pin is sampled low;
User-defined bit (Bank 4, Index 53h, bit 5) is written to 1.
STATUS
STATUS
CLEAR
CLEAR
Caseopen Detection
BEEP Alarm Function
Figure 8-24 Caseopen Mechanism
W83627DHG-P/W83627DHG-PT
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Publication Release Date: July 09, 2009
Version 1.94